This type of use is relatively common, especially in the motor-vehicle industry where an anti-theft lock conventionally makes it possible to block the steering column of a vehicle when its driver leaves it. For such a use, the bolt of the lock is controlled by a key in such a way as to be displaceable in a fixed case approximately perpendicular relative to the axis of a shaft of the steering column, in order to engage with or disengage from a receptacle of a keeper integral in terms of rotation with the shaft. In this type of anti-theft lock, it is relatively common to produce a keeper which takes the form of a tubular sleeve or of two semicylindrical half-shells which are attached to the shaft and fastened to the latter so as to be integral with this in terms of rotation. This fastening is usually obtained by welding. Such a keeper is equipped, on its periphery, with a receptacle generally approximately parallel to the generatrices of the shaft, into which the bolt of the lock controlled by the key can engage.
The manufacture of such locks, especially of the keeper, presents many problems, particularly because the shaft of the steering column to which it is intended to be secured has to conform to relatively standardized specifications. This is true especially of the inside and outside diameters and therefore of the thickness of the hollow shaft and the grades of the material from which this shaft is made. Under such conditions, the fastening of a keeper to a relatively thin hollow shaft presents technical problems in manufacturing terms and economic problems in terms of cost.